b-u bbb bbf bbk bbo bbr bbs bbu bfb bff bfo bfr bfs bfu bkb bkf bkk bko bkr bks bob bof bok boo bor bos bou brb brf brk bro brr brs bru bsb bsf bsk bso bsr bss bsu bub buf buk buo bur bus buu fbb fbf fbk fbo fbr fbs fbu fff ffk ffo ffr ffs ffu fkb fkf fkk fob fof fok foo for fos fou frb frf frk fro frr frs fru fsb fsf fsk fso fsr fss fsu fub fuf fuk fuo fur fus fuu kbb kbf kbk kbo kbr kbs kbu kff kfo kfs kfu kkb kkk kkr kks kku kob kof kok koo kor kos kou krf krk kro krr krs kru ksb ksf ksk kso ksr kss ksu kub kuk kur kus kuu ob- obb obf obk obo obr obs obu of- ofb off ofo ofr ofs ofu okb okk oko okr oks oku oo- oob oof ook ooo oor oos or- orb orf ork oro orr ors oru os- osb osf osk oso osr oss osu ou- ouf ouk ouo our ous rbb rbf rbk rbo rbr rbs rbu rfb rff rfk rfo rfr rfs rfu rkb rkf rkk rko rks rku rob rof rok roo ror ros rou rrb rrf rrk rrr rrs rru rsb rsf rsk rso rsr rss rsu rub ruf ruk ruo rur rus ruu sbb sbf sbk sbo sbr sbs sbu sfb sff sfk sfo sfr sfs sfu sk- skb skf skk sko skr sks sku sob sof sok soo sor sos sou sr- srb srf srk sro srr srs ss- ssb ssf ssk sso ssr sss ssu sub suf suk suo sur sus suu ubb ubf ubk ubo ubr ubs ubu uff ufo ufr ufs ufu ukb ukf ukk ukr uku uob uok uoo uor uos ur- urb urf urk uro urr urs uru usb usf usk uso usr uss usu uur uus uuu

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b-r-k bbook bbuss bo-bo bobko bobok bobos bobr boffo boffs bokko bokok bokor boobs boofs booko books boors booru borbo borko borks borku boro- borok boroo boros borou borro borsk borsu borus bosko bosks bosor bossk bosso bouko bouks bours brobo brobs brook broos bross brouk brous brrrr bruff brusk bruss bsous buffo buffs bufos bukk- bukor burbs burks buroo buros burro burrs burru buruk burus busks busso bussu busur busuu fofos fokus fooks forbs forks foros forro forso forss forur forus fourb fouro fours frobs frosk fruko fu-fu fubbs fubus fuffs furbo furo- furor furrs furus fuso- fusor fusus k-rob ko-ko kobos kobru kobuk kobus koffs kokko kokor kokos kokou koksu kokur kooks kooru korbo korff korku koror koros korro korso koruk korus kosku kosor kosso koufu kours kroos kross krsko ksour kubok kubos kuffs kukko kukok kuksu kukur